The present invention relates to apparatus for previewing, editing, projecting, and sorting photographic slides, and more particularly, to an apparatus for stack-loading slides into a slide projector.
Several types of modern photographic slide projectors utilize slide trays. The slide trays are generally made of plastic with spaced compartments for holding individual slides. During projection the slides in the compartment are sequentially removed from the compartment by the slide projector mechanism and transported inside the projector for projection. After projection, the slide is transferred back to the tray and the next sequential slide is selected. Slide trays may be either linear or circular in shape.
U.S. Pat. No. 3,276,314 "Automatic Slide Projector," assigned to Eastman Kodak Company, which issued on Oct. 4, 1966, to H. T. Robinson, describes an automatic slide projector known by the Kodak trademark "Carousel" projector. Carousel projectors have a reputation for reliability. This reliability is achieved by utilizing a slide tray which holds slides individually in separate compartments, so that they do not touch each other and bind. Slides are placed into the tray from above. Slides are dropped into the projector through a slide gate in the projector from an opening in the bottom of the tray by force of gravity and by means of a slide lifter which lowers the slide through the gate into the projector. After projection, the lifter moves the slide up through the gate into the compartment in the tray and the entire circular tray is rotated so that the next slide compartment is positioned over the slot.
This mechanism results in very reliable operation because the slides are held vertically at all times from the compartment in the tray to the projection station within the projector.
Kodak also sells a stack loader for use with its Carousel projectors. The stack loader allows up to forty slides to be projected without using a slide tray. The slides in the stack loader are stacked on end in the Kodak stack loader. Since the slides are not held in separate compartments they have a tendency to stick to one another, so that sometimes a slide will not drop into the projector or will not come entirely out of the projector. This causes jamming and interruption of projection. Also, the Kodak stack loader will accept only forty slides at a time. More slides cannot be inserted until the stack loader has emptied itself, so that continuous, uninterrupted projection of more than forty sequential slides is not possible. Furthermore, editing and sorting of slides is not possible at all with the Kodak stack loader.
U.S. Pat. No. 4,249,329 entitled "Apparatus for Viewing and Sorting Photographic Slide Transparencies," of Owen L. Lamb, which issued on Feb. 10, 1981, discloses an apparatus for previewing and sorting slides, but no means are provided for loading the slides into a projector.
U.S. Pat. No. 4,338,738 entitled "Slide Previewer and Tray Loader", which was granted to Owen L. Lamb on July 13, 1982, discloses an apparatus for previewing slides and for loading the slides into a slide tray, but no means are provided for loading the slides into a projector and for sorting slides removed from the projector.
It is an object of the present invention to provide a slide-handling device which can be used to preview and edit slides, load and unload a slide projector, and sort the slides.
It is a further object of this invention to provide a slide previewer, sorter, and stack loader which operates primarily by force of gravity, thereby eliminating the need for complicated mechanisms.
It is a further object of this invention to provide a stack loader in which any number of slides can be sequentially projected without interruption.